14 M. FOSLIE [1899' 



Børgesen^) as Melohesia sp., and recorded by Simm ons^) 

 under the name of M. macrocarpa Rosan. stands very near to the 

 present spedes. The latter remarks 1. c. that this alga „wåchst 

 an den fåroischen Kiiste auf Gigartina mamillosa die fast immer 

 mit einer Melobesiakruste bedeckt ist. Auf Chondrus crispus fand 

 ich sie nicht einmal, wenn diese beiden Algen zusammen vvuchsen". 

 Through the kindness of Mr. Børgesen I have had the oppor- 

 tunity of examining vvell developed specimens attached to the said 

 host. Rosanoff met vvith his M. macrocarpa only on Phyllo- 

 phora rubens, and Farlow quotes the same spedes from the 

 coast of xAmerica attached to Chondrus crispus. 



In List of Lith. I subsumed M. macrocarpa under D. piistu- 

 latum. Cp. some new or er. Liih. p. 18. I have seen but a very 

 small fragment of an authentic D. macrocarpum and if it in fact^ 

 as remarked by Rosanoff, differs from D. pustulatum only as- 

 regards the sporangia, it scarcely may be considered specifically 

 distinct However, judging from the said minute fragment with a 

 solitary conceptade I suppose that t::e spedm.ens whidi underlie^ 

 Rosanoffs description have been young, and a rather great dif- 

 ference between young and old specimens is often to be seen even 

 within Dermatolitlion as well as Melohesia, f. inst. M. zonalis. 



The vertically elongated basal cells in D. macrocarpum are 

 quoted to be but twice as long as broad. In the said form from 

 the Faroe islands the crust is up to 300 p- thick, with 6 — 8 layers 

 of cells, and here the basal cells are as a rule considerably longer 

 than broad, or 60 — 80 jj- high, but perhaps more varying than the 

 examined parts of a specimen show. The upper cells appear 

 not to be much varying, and are also vertically elongated. I found 

 them frequently 20- 30 /Jt high. The conceptacles of sporangia are 

 subconical though often but little prominent, frequently 450—550 

 IJL in diameter seen from above. The sporangia are bisporic, 

 90—140 p- long by 50 — 75 /i. Thus the present form much dif- 



1) F. Børgesen & C. Osten fe Id-Han sen. Planter samlede paa Færøerne 

 i 1895. Botan. Tidsskr. Bd. 20. Kjøbenhavn 1896. 



2) Hermann G. Simmons. Zur Kenntniss der Meeresalgen-Flora der Får- 

 oer. Hedwigia Bd. 36. 1897. Pag. 268. 



